Sergio Combined Treatment with Bases = Cold Restoration (to achieve density, hydration, and a stunning visual effect) with a wear duration of 2-4 weeks • Wash hair twice with a preparatory shampoo, pH 5.5-6.0 • Dry to 50% • Apply an amino acid mask generou... amino acid mask cold restoration hair care routine hair density hair treatment hydration leave-in cream lipid mask Apr 27, 2026